<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<script>
/*
    .  匹配任意字符 除了回车和换行
    \. 匹配一个点
    
    |  择一匹配 (管道符号)
    
 */
var re = /ab|ac/g;
s = "ac"
console.log(re.test(s));


</script>
</body>
</html>